package com.szh.zx.gaoDingJavaBook.chapter8.six;

import java.util.HashMap;
import java.util.HashSet;

public class NullHashMap {
	public static void main(String[] args) {
		HashMap hashMap = new HashMap();
//		视图将两个key为null的值的key-value 对放入hashmap
		hashMap.put(null,null);
		hashMap.put("s",null);
		System.out.println(hashMap);
	}
}
